In GSD I, Lasso retained lactate (β = - 0.682), glucose (β = - 0.625), and IGF1 SDS (β = 0.524), and bootstrap validation showed only IGF1 SDS remained consistently significant.<h4>Conclusions</h4>Hyperlactatemia is significant predictor of growth impairment in GSD, while IGF1 is a stable predictor in GSD I. These findings highlight metabolic and hormonal targets for future hypothesis-driven research in this population. Here, IGF1 is linked to disorder of glycogen metabolism.